Speaking at the launch of Sky’s new drama season, Radcliffe is also reported to have said that Potter co-stars Emma Watson and Rupert Grint would not be involved in the Fantastic Beasts and Where To Find Them film either.

“Needless to say I wouldn’t be involved, and I guess none of the others will be, but I know nothing about it,” said the star, 24.

She said: "The laws and customs of the hidden magical society will be familiar to anyone who has read the Harry Potter books or seen the films, but Newt's story will start in New York, seventy years before Harry's gets underway."

Based on the adventures of fictional author Newt Scamander, the new film is expected to be the first in a series.

More than 450 million copies of her seven Potter books have been sold and the films made stars of Radcliffe, Watson and Grint.

Rowling’s adult novel The Casual Vacancy is being turned into a TV serial by the BBC.